1. Field of the Invention
The present invention relates generally to encapsulated window assemblies comprising a polymeric frame or gasket member surrounding peripheral regions of a glass sheet and, in particular, to encapsulated window assemblies such as vehicle roof panels including a preformed, molded-in-place periphery seal. The invention also relates to the mold and process used in forming such window assemblies.
2. Related Art
Initially, fixed window assemblies for vehicles were comprised of a plurality of elements including adhesive elements applied around the marginal edges of the glass sheet, suitable mechanical fasteners such as metal clips, and exterior decorative trim strips disposed to cover the marginal edges of the glass sheet and the adjacent portions of the vehicle frame. Such window structures were costly, especially from a labor standpoint, since it was necessary to assemble the individual elements along the vehicle assembly line.
Subsequently, in an endeavor to improve the above window structure, unitary window assemblies of the type illustrated in U.S. Pat. No. 4,072,340 were developed. These assemblies included a sheet of glass, an adjacent frame, and a casing or gasket of molded material, such as poly(vinyl chloride), extending between the frame and peripheral edge of the window to hold the sheet of glass and the frame together. Fasteners were provided at spaced locations along the frame such that the entire assembly could be guided into location over the opening in a vehicle body as a unit. Other types of unitary window assemblies are disclosed in U.S. Pat. Nos. 3,759,004 and 4,364,595. While such unitary window structures gradually reduced the time required to mount the window assembly in the associated vehicle, such structures were relatively costly, since the individual components required to produce each window unit generally required manually assembly.
In a further development, single sheets of glass and laminated glass assemblies were formed with integral frame or gasket members molded by a reaction injection molding (RIM) process. U.S. Pat. No. 4,561,625 is illustrative of such a process and resulting product, and is incorporated herein by reference. Such an assembly can be readily attached to the material defining the periphery of a window opening, for example, during the manufacturing of a vehicle. Typically, the frame or gasket member is formed of a polyurethane material.
In the case of certain moveable window assemblies, such as vehicle roof panels, elastomeric periphery seals have been used to insure a watertight seal between the window assembly and the window opening. Where such periphery seals have been used, they have typically been secured to the gasket member of the window assembly following the molding process, using either double-sided adhesive materials or "snap-fit" type mechanical interlocking means. Both of these methods require relatively expensive post-molding, labor intensive procedures, may result in gaps between the periphery seal and the gasket member and therefore an incomplete seal, and are prone to the eventual separation of the periphery seal from the gasket member.
It has recently been proposed to provide a periphery seal which is molded in place to the gasket member. Such a periphery seal is illustrated, for example, in U.S. Pat. No. 5,344,603. This patent describes a process for producing a window assembly with a peripheral seal for vehicle roofs in which a glass sheet 10, a support member 12 and a profile part 13 are inserted in a mold, the profile part 13 being positioned by upper and lower attaching projections 6 and 7. An elastomeric material 9 is then introduced into the mold. A seal 16 may be molded directly on the profile part 13 prior to the injection molding of the elastomer 9.
Despite the above-described improvements in encapsulated window assemblies, a further improved process and mold for use in forming such window assemblies is desired.